Primary bladder neck obstruction in men: The importance of urodynamic assessment and cystourethrography in measuring its severity.

Abstract

Primary bladder neck obstruction (PBNO) is a condition primarily affecting young men, characterized by obstruction at the bladder neck, leading to lower urinary tract symptoms. The aim of this study was to identify a correlation between the severity of bladder neck opening impairment and urinary symptoms by means of urodynamic studies. A retrospective analysis was conducted in adult males diagnosed with PBNO at a university neurourology department between 2015 and 2022 who underwent voiding cystourethrography (VCUG) and pressure-flow studies. The cohort was divided into two groups: absence of bladder neck opening on VCUG (Group A) and incomplete bladder neck opening (Group B). Out of the 82 patients with PBNO screened, 53 were included in the analysis. Nocturia was the only symptom more prevalent in Group A (65% in Group A vs. 30% in Group B, p = 0.02) but scores and subscores of the Urinary Symptom Profile questionnaire were not different between groups. In addition, the detrusor pressure at a maximum flow rate (PdetQmax), bladder outlet obstruction index (BOOI), and bladder contractility index (BCI) were higher in Group A than in Group B [PdetQmax (A = 93.7 ± 53.7 cmH2 O vs. B = 65.7 ± 26.4 cmH2 O; p = 0.01)-BOOI (A = 77 ± 58.3 vs. B = 48 ± 25.7; p = 0.03)-BCI (A = 136 ± 51.3 vs. B = 110 ± 41.7; p = 0.04)]. This study demonstrates a significant association between the extent of bladder neck opening impairment observed on VCUG and obstruction and contraction urodynamic parameters, but no association with the severity of urinary symptoms. Future studies should evaluate the predictive value of treatment response and the occurrence of complications based on clinical and urodynamic parameters.